﻿<!DOCTYPE html>
<html>

<head lang="en">
    <meta charset="UTF-8">
    <title></title>
    <style>
        .wrap {
            width: 400px;
            height: 400px;
            margin: 100px auto 0;
        }

        .wrap h1 {
            text-align: center;
        }

        .wrap div {
            width: 400px;
            height: 300px;
            background: pink;
            font-size: 30px;
            text-align: center;
            line-height: 300px;
        }
    </style>
    <script src="./jquery-1.11.1.js"></script>

<body>

    <div class="wrap">
        <h1>按键改变颜色</h1>
        <div id="bgChange">
            keyCode为：
            <span id="keyCodeSpan"></span>
        </div>
    </div>
    <script>
        $(function () {
            $('#bgChange').ready(function () {
                $(document).on('keydown', function (e) {
                    $("#keyCodeSpan").text(e.keyCode)
                    switch (e.keyCode) {
                        case 66:
                            $("#bgChange").css("background", "blue");
                            break;
                        case 82:
                            $("#bgChange").css("background", "red");
                            break;
                        case 89:
                            $("#bgChange").css("background", "yellow");
                            break;
                        case 80:
                            $("#bgChange").css("background", "purple");
                            break;
                        case 83:
                            $("#bgChange").css("background", "skyblue");
                            break;
                        case 71:
                            $("#bgChange").css("background", "green");
                            break;
                        case 79:
                            $("#bgChange").css("background", "orange");
                            break;
                        default:
                            $("#keyCodeSpan").text("无此键位");
                            $("#bgChange").css("background", "pink");
                    }
                })
            })
        })
    </script>
</body>

</html>